Field of the Invention
The invention relates to a method of fabricating connector terminals to be used for electrical connection between devices equipped in an automobile, for instance. The invention relates further to an electrically conductive metal sheet to which the method is applied
Description of the Related Art
In a process of fabricating a relay connector terminal including a plurality of terminals each having at one of ends thereof a contact portion, and at the other end a male tab, the terminals are put in a line within a pair of dies, and then, are fabricated by die-casting, in order to effectively carry out the process.
A relay terminal to be compressed into an object is made of a thin metal sheet, and is designed to have a male tab made of a folded metal sheet to cause the male tab to have an increased thickness. Thus, the male tab can have a designed thickness and a sufficient rigidity.
FIG. 14 is a broken perspective view of the electric connector suggested in Japanese Utility Model Publication No. 3156761.
The electric connector 500 illustrated in FIG. 14 includes an electrically insulative body 501, a plurality of terminals 502 fixed to the body 501, a fixing unit 503 to which the body 51 is fixed, and a housing 504 covering the body 501 therewith.
The body 501 is formed with a plurality of holes 510 through which the terminals 502 are inserted. Each of the terminals 502 includes a contact portion 520, a central portion 521 at which the terminal 502 is fixed in the hole 510, and a rear portion 522. The rear portion 522 includes an inclining portion 523, and a connection portion 524 at which the terminal 502 is soldered to an object. Since each of the terminals 502 is designed to include the inclining portion 523, a pitch between the adjacent connection portions 524 is greater than a pitch between the adjacent contact portions 520.
FIG. 15 is a plan view of the electric connector suggested in Japanese Utility Model Application Publication No. H03 (1991)-116572.
The electric connector includes a female connector, and a male connector detachably coupled to the female connector.
FIG. 16 is a perspective view of a part of the male connector 600, and FIG. 17 is a cross-sectional view of the male connector 600.
As illustrated in FIGS. 15 to 17, the male connector 600 is formed at a proximal end 600a thereof with a plurality of standing walls 600b and 600c in which a stripped portion 620a of a cable 620 is compressed to thereby be fixed. The male connector 600 includes a guide 600d having a rectangular cross-section. The male connector 600 is formed at a front end thereof with a contact portion 601. As illustrated in FIG. 17, the contact portion 601 is made of a flat metal sheet folded into two layers, in which ends 601a of the two layers align with each other.
In a terminal as a part of a relay connector terminal, it is necessary to design a contact portion to be made of a thin metal sheet in order to provide requisite elasticity to the contact portion. In contrast, it is necessary to design a male tab to be made of a thick metal sheet in order to allow the male tab to have both a predetermined thickness and a requisite rigidity.
To this end, a conventional terminal was designed to be made of metal sheets having different shapes from one another, or to include a contact portion pressed to have a reduced thickness. However, these conventional processes are accompanied with problems that the fabrication costs are unavoidably increased in the former, and the elasticity of the contact portion is lowered in the latter because of hardening of a metal sheet caused by being pressed. The latter is accompanied further with a problem that since a metal sheet from which the contact portion is fabricated has to be wider if the metal sheet had a smaller thickness, it is necessary to carry out an additional step of controlling a width of the metal sheet into a designed width.
Furthermore, in the case that a relay terminal to be compressed into an object is designed to include a male tab fabricated by folding a metal sheet to thereby have a predetermined increased thickness, a step of bending a metal sheet has to be carried out in a plurality of times in the process of fabricating the male tab, and hence, it is difficult to enhance an efficiency of the process.
The problems mentioned above are not able to be solved by the above-mentioned conventional electric connectors illustrated in FIGS. 14 to 17.